Need help with physics question about relative motian.

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SUMMARY

The discussion centers on a physics problem involving two identical cars, Dagwood and Blondie, where Blondie is traveling at twice Dagwood's speed. When both apply equal constant braking force, Dagwood stops after a time T and distance D. The conclusion drawn is that Blondie will take 2T to stop, based on the assumption that time to stop is directly proportional to speed. However, further clarification is needed regarding the deceleration of both cars to validate this conclusion.

PREREQUISITES
  • Understanding of kinematics, specifically the equations of motion.
  • Knowledge of constant acceleration and deceleration concepts.
  • Familiarity with the relationship between speed, time, and distance.
  • Basic algebra for solving equations related to motion.
NEXT STEPS
  • Review the equations of motion for constant acceleration.
  • Study the principles of relative motion in physics.
  • Explore the concept of deceleration and its effects on stopping distances.
  • Practice solving similar physics problems involving braking distances and times.
USEFUL FOR

Students studying physics, educators teaching kinematics, and anyone interested in understanding the dynamics of motion and braking in vehicles.

bonbloc
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Homework Statement


Dagwood and Blondie are driving two identical cars. Blondie is passing Dagwood at twice his speed. They apply their brakes with equal constant force and stop on the level road. Dagwood travels a distance D in a time T while braking. How long does Blondie take to stop?
b) how far does Blondie travel while stopping?

for question 1a) i got 2 T, because Blondie was going twice Dagwoods speed she would take twice as much time to slow down but i am not sure if i am right.
 
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Hi, bonbloc. Welcome to PF!

No freebies here. According to the rules of the forum, you need to complete items 2 and 3 before receiving help.
 
bonbloc said:
for question 1a) i got 2 T, because Blondie was going twice Dagwoods speed she would take twice as much time to slow down but i am not sure if i am right.

In order to be certain, you need to come up with a good mathematical argument. Does each car have the same deceleration? Can you give a reason for your answer?
 

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